<template>
  <div class="liveDetail">
    <div class="live_header">
      <span>{{ objList.name }}的直播间</span>
      <span>春季美妆搭配</span>
      <span></span>
    </div>
    <div class="camera_outer">
      <video
        id="videoCamera"
        :width="videoWidth"
        :height="videoHeight"
        autoplay
      ></video>
      <canvas
        style="display: none"
        id="canvasCamera"
        :width="videoWidth"
        :height="videoHeight"
      ></canvas>
      <div v-if="imgSrc" class="img_bg_camera">
        <img :src="imgSrc" alt="" class="tx_img" />
      </div>
    </div>
    <div class="button">
      <button @click="getCompetence()">打开摄像头</button>
      <button @click="stopNavigator()">关闭摄像头</button>
    </div>
    <div class="goBack">
      <p @click="$router.go('/live')">返回</p>
      <p @click="stopNavigator()">强制返回</p>
    </div>
    <!-- <button @click="setImage()">拍照</button> -->
  </div>
</template>

<script>
export default {
  data() {
    return {
      id: null,
      objList: {},
      videoWidth: 300,
      videoHeight: 300,
      imgSrc: "",
      thisCancas: null,
      thisContext: null,
      thisVideo: null,
    };
  },
  createElement() {
    this.getCompetence();
  },
  mounted() {
    this.getCompetence();
  },
  methods: {
    getDetailList() {
      this.$http.get(`/live/${this.id}`).then((res) => {
        if (res.data.code === 1) {
          this.objList = res.data.data;
        }
      });
    },
    getCompetence() {
      var _this = this;
      this.thisCancas = document.getElementById("canvasCamera");
      this.thisContext = this.thisCancas.getContext("2d");
      this.thisVideo = document.getElementById("videoCamera");
      // 旧版本浏览器可能根本不支持mediaDevices，我们首先设置一个空对象
      if (navigator.mediaDevices === undefined) {
        navigator.mediaDevices = {};
      }
      // 一些浏览器实现了部分mediaDevices，我们不能只分配一个对象
      // 使用getUserMedia，因为它会覆盖现有的属性。
      // 这里，如果缺少getUserMedia属性，就添加它。
      if (navigator.mediaDevices.getUserMedia === undefined) {
        navigator.mediaDevices.getUserMedia = function (constraints) {
          // 首先获取现存的getUserMedia(如果存在)
          var getUserMedia =
            navigator.webkitGetUserMedia ||
            navigator.mozGetUserMedia ||
            navigator.getUserMedia;
          // 有些浏览器不支持，会返回错误信息
          // 保持接口一致
          if (!getUserMedia) {
            return Promise.reject(
              new Error("getUserMedia is not implemented in this browser")
            );
          }
          // 否则，使用Promise将调用包装到旧的navigator.getUserMedia
          return new Promise(function (resolve, reject) {
            getUserMedia.call(navigator, constraints, resolve, reject);
          });
        };
      }
      var constraints = {
        audio: false,
        video: {
          width: this.videoWidth,
          height: this.videoHeight,
          transform: "scaleX(-1)",
        },
      };
      navigator.mediaDevices
        .getUserMedia(constraints)
        .then(function (stream) {
          // 旧的浏览器可能没有srcObject
          if ("srcObject" in _this.thisVideo) {
            _this.thisVideo.srcObject = stream;
          } else {
            // 避免在新的浏览器中使用它，因为它正在被弃用。
            _this.thisVideo.src = window.URL.createObjectURL(stream);
          }
          _this.thisVideo.onloadedmetadata = function (e) {
            _this.thisVideo.play();
          };
        })
        .catch((err) => {
          console.log(err);
        });
    },
    //  绘制图片（拍照功能）
    setImage() {
      var _this = this;
      // 点击，canvas画图
      _this.thisContext.drawImage(
        _this.thisVideo,
        0,
        0,
        _this.videoWidth,
        _this.videoHeight
      );
      // 获取图片base64链接
      var image = this.thisCancas.toDataURL("image/png");
      _this.imgSrc = image;
      this.$emit("refreshDataList", this.imgSrc);
    },
    // base64转文件
    dataURLtoFile(dataurl, filename) {
      var arr = dataurl.split(",");
      var mime = arr[0].match(/:(.*?);/)[1];
      var bstr = atob(arr[1]);
      var n = bstr.length;
      var u8arr = new Uint8Array(n);
      while (n--) {
        u8arr[n] = bstr.charCodeAt(n);
      }
      return new File([u8arr], filename, { type: mime });
    },
    // 关闭摄像头
    stopNavigator() {
      this.thisVideo.srcObject.getTracks()[0].stop();
    },
  },
  beforeRouteLeave(to, from, next) {
    if (to.path === "/live") {
      this.stopNavigator();
    }
    this.$router.push("/live");
  },
  created() {
    this.id = this.$route.params.id;
    this.getDetailList();
  },
};
</script>

<style scoped>
.liveDetail {
  width: 100%;
  height: 100%;
}
.liveDetail > .button {
  display: flex;
  position: absolute;
  top: 60%;
  right: 47%;
  align-items: center;
  justify-content: center;
}
.liveDetail > .goBack {
  display: flex;
  position: absolute;
  top: 70%;
  right: 40%;
  align-items: center;
  justify-content: center;
}
.liveDetail > .goBack p {
  width: 180px;
  height: 50px;
  margin-right: 20px;
  line-height: 50px;
  text-align: center;
  color: #fff;
  background: rgba(0, 0, 0, 0.3);
}

.liveDetail > .goBack p:first-child {
  background: red;
}
.liveDetail > .button button {
  padding: 5px 10px;
  margin-right: 10px;
}
.live_header {
  width: 100%;
  height: 60px;
  background: #666;
  display: flex;
  align-items: center;
  padding: 0 20px;
  justify-content: space-between;
  color: #fff;
}

.live_main {
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.8);
}
.lives_mains {
  width: 100%;
  height: 80%;
  display: flex;
  color: royalblue;
}
.live_footer {
  width: 500px;
  height: 50px;
  display: flex;
  text-align: center;
  margin-top: 10px;
  justify-content: space-around;
}
.live_footer span {
  width: 200px;
  color: #fff;
  padding: 0 20px;
  text-align: center;
  line-height: 50px;
  border: 1px solid red;
}
#videoCamera {
  width: 80%;
  height: 50%;
}
.main_left {
  width: 30%;
  display: flex;
  flex-wrap: wrap;
  text-align: center;
  padding: 20px 0;
}
.main_right {
  padding: 10px;
  flex: 1;
}
.main_right img {
  width: 500px;
  height: 400px;
}
.main_left span {
  width: 100%;
  height: 50px;
  line-height: 50px;
}

.camera_outer {
  width: 100%;
  height: 100%;
  display: flex;
  justify-content: center;
  position: relative;
  overflow: hidden;
  background-size: 100%;
  background: #999;
}

.camera_outer video,
.camera_outer canvas,
.tx_img {
  -moz-transform: scaleX(-1);
  -webkit-transform: scaleX(-1);
  -o-transform: scaleX(-1);
  transform: scaleX(-1);
}
.btn_camera {
  position: absolute;
  bottom: 4px;
  left: 0;
  right: 0;
  height: 50px;
  background-color: rgba(0, 0, 0, 0.3);
  line-height: 50px;
  text-align: center;
  color: #ffffff;
}
.bg_r_img {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  top: 0;
}
.img_bg_camera {
  position: absolute;
  right: 0;
  top: 0;
}
.img_bg_camera img {
  width: 300px;
  height: 300px;
}
.img_btn_camera {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 50px;
  line-height: 50px;
  text-align: center;
  background-color: rgba(0, 0, 0, 0.3);
  color: #ffffff;
}
.img_bg_camera .loding_img {
  width: 50px;
  height: 50px;
}
</style>
